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Number 17 |
- Welcome Page 2 - Update Page 3 - News Page 4 - Brief lines | Welcome to this issue of 2PDM, an e-zine distributed every two weeks on a free subscription basis. The following article, 'Tolerance', is the fifth of a series of articles by Mike Bryan about CAD Data Exchange. The first article, 'A Logical Approach to CAD Data Exchange' appeared in the November 6, 2000 issue. The second, 'Determine Minimum Dataset' appeared in the December 4, 2000 issue, the third, 'Choose the Exchange Format',in the January 15, 2001 issue, and the fourth, 'The Tony Blair Imperative'in the February 12, 2001 issue. * Tolerance * I read an interesting article a few weeks ago entitled 'The Billion Dollar Data Exchange Problem'. This claimed that the greatest cause of data exchange problems, particularly with solids, was tolerance. Now tolerance is a function of the internal working precision of the CAX system. One of the worst systems I ever worked with, from a working precision point of view, was an early version of mainframe CADAM. If this was used purely as an electronic drawing board all well and good. The strength of this version lay in its speed not its accuracy and to this end it even had its own trig functions. If you defined, say, a 2" square, not aligned with the major axes, then flipped it about one of its edges, after less than a dozen flips there would be no geometry visible on the screen. I have to say that this did not give you a whole bunch of confidence especially when you started working with big numbers. A little late in the day a double precision option was offered and it helped slightly. Accompanying that system at the wrong end of the accuracy spectrum is, of course, manual drafting. I worked on the drawing board for fifteen years and with a well-sharpened 2H pencil I reckoned I could draw to an accuracy of 0.01" (ten thou) - only marginally worse than that system. CAD was never about speed - it was always about accuracy. Everybody who understands this can get very excited at the prospect of being able to define geometry to thirteen significant figures. I stated above that tolerance is a function of the accuracy, or working precision, of the system. What this really boils down to is that when the separation between two distinct points falls below some threshold then the system deems the two points to be coincident - this threshold is the tolerance. Obviously, the greater the internal precision, the smaller the tolerance can be. Unhappily, some CAX systems still sacrifice accuracy for speed so that, for example, what one system thinks is a valid solid another system thinks is a self-intersecting solid. Naturally this spells all sorts of problems for data exchange. On another occasion, I was involved in transferring surface models from CATIA to Computervision for Computational Fluid Dynamics analysis using both a direct translator and IGES (IGES proved to be better). The CV user had to redefine a fair amount of the surface geometry because the CFD code was expecting a far greater precision than CATIA was offering. About six or seven years ago a project called AeroSTEP was running which involved three aero-engine companies exchanging solids models with Boeing, using STEP AP203, to assist in the creation of a digital mock-up of the 777. The results were good enough to encourage Boeing to publish a Memorandum Of Understanding And Co-operation, albeit only for digital mock-up quality data. This Memorandum stated that Boeing would accept CAD data in STEP format rather than insist on CATIA models. The one real problem identified was tolerance. The systems involved were CV, Unigraphics and CATIA. Do we need thirteen significant figures of working precision or more? Yes absolutely. When defining aircraft geometry it is usual to place the axis system at some point in front of the forward fuselage and this can result in some very large numbers. Computational round-off errors on such numbers can soon eat away at the number of significant figures. The greater the precision of the original geometric model the better since we can easily reduce precision when necessary but we cannot increase it. There will always be reductions in precision when transferring geometric data between dissimilar systems because of computational round-off errors therefore it is imperative that the initial precision be as high as possible. We should not forget that algorithms used in geometric definition are vitally important too in respect of precision. For instance, how is a surface/surface intersection computed? A company might have more confidence in the result if it had some details such that it could satisfy itself that the algorithm was well found and robust. On a much more mundane level how confident are we of the accuracy of the definition, say, of a circular arc? Should we worry ourselves about such things? Well unfortunately, yes we should. A few years ago, the company where I was then employed received, during an ISO 9001 audit, a non-compliance on a Co-ordinate Measuring Machine. Nothing at all to do with the mechanics of the machine but about its software. Had the software been checked with respect to the accuracy of its geometric definition? For instance, when the software described a circular arc how accurate was it? Did we have a document tabulating the errors? Well of course we didn't but some pretty quick research showed us that this problem was known and tables of checking data had been prepared for most common geometric shapes by the UK's National Physical Laboratory and submitted to BSI for consideration as a standard. I would be most interested to hear if anyone out there has come up against this and actually checked the geometric construction accuracy of any of the well-known CAD systems. So, when transferring data between two systems, as well as the tolerance mismatch and conversion round-off errors of the pre and post-processors, we also have to contend with the probable geometric construction errors of both systems. But, looking on the bright side, it is still more accurate than manual drafting. Mike Bryan can be contacted at m.bryan@chyanbre.demon.co.uk |
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News |
Ariba, Inc. and Agile Software Corporation announced that, due to the challenging economic and market conditions, they have mutually agreed to terminate their proposed merger agreement without payment of any termination fees. Dassault Systemes announced the signing of an agreement whereby it plans to acquire the privately held SRAC through a stock transaction for the amount of $22 Million. Barbara Guerra, formerly vice president of SRAC, will be CEO of the new subsidiary. SDRC announced that it has acquired Inovie Software, Inc., a provider of Web-based, peer-to-peer collaborative project management software. SDRC will immediately begin to couple Inovie's project management software with its collaborative product management solutions. * Financial * Ingenuus Corporation reported first quarter 2001 revenues of $707,000 compared with revenues of $310,000 for first quarter 2000. * People * Cadence Design Systems, Inc. announced the appointment of Spencer Clark as vice president and dean of Cadence University, the corporate education arm of the company. MatrixOne, Inc. announced the opening of its Asia-Pacific headquarters in Singapore. Andy Kalambi is vice president and managing director for the Asia-Pacific region.  * Implementation * Agile Software Corporation announced that Microsoft's Xbox video game system division has selected Agile to provide its collaborative manufacturing solution. Centric Software announced that the Volvo Cars Monitoring and Concept Center (VMCC) has made a strategic decision to deploy Centric Innovation. Dassault Systemes announced that Lamborghini has selected CATIA Solutions as its strategic computer-aided design, manufacturing, and engineering (CAD/CAM/CAE) system. Framework Technologies Corp. announced the results of a recent study in which ActiveProject helped Pemco, Inc. reduce prototype time from 48 to seven months on a new envelope machine, as well as delivered the project under budget. Pemco is a manufacturer of packaging equipment for the paper industry. Informative Graphics Corp. announced that its Brava! solution has been adopted by ProjectOnNet.com, an application service provider, to deliver construction-based information to subscribers around the world. Innoveda, Inc. announced that OSRAM, the international producer of lamps and electronic control devices, is standardizing on the Innoveda EDA environment for PCB design. MatrixOne, Inc. announced that it has been awarded a contract by Entegris, Inc., the materials integrity management company. MatrixOne's eMatrix software will enable Entegris to upgrade its product development processes and more efficiently manage product data. Oculus Technologies Corp., a peer-to-peer innovator providing software solutions to help corporations save time and money through better decision-making, announced that Ford Motor Company has piloted Oculus CO. The Ford team utilized Oculus CO to seamlessly connect geographically dispersed design team members working with different software applications, on disparate operating systems. PTC announced that it has entered into a multi-million dollar two-year research and development, cost-sharing agreement with the U.S. Army's NAC (Warren, MI). The initial phase includes services and 4,000 licenses for Windchill software. NAC is the focal point for automotive collaborative research and development within the U.S. Army's Tank-automotive and Armaments Command. think3 announced that Marcolin has selected think3's flagship solid and surface modeling software, thinkdesign, as its standard for 3-D design of fashion eyeglasses, with a goal of increasing productivity and reducing time-to-market. TransCAT GmbH, a wholly-owned subsidiary of RAND Worldwide, announced that EADS Airbus GmbH has purchased TransCAT's Q-Checker software to contribute in the company's development of its new A380 aircraft. UGS announced that DaimlerChrysler Corporation has selected the e-Vis collaboration solution from UGS to automate the real-time sharing of manufacturing related quality data across the Jeep platform team and supply chain. UGS announced a software and services contract with Decathlon - a French manufacturer and distributor of sports equipment and apparel - for the supply and implementation of 125 licenses of i-Man, UGS' internet-centric software product used to manage product content for collaborative commerce. UGS announced that Angelus Sanitary Machine Co. has selected Solid Edge to design its global line of can sealing machines. Angelus purchased 31 licenses of the 3-D solid modeling software to replace its existing, outdated 2-D CAD system. The company will use Solid Edge with Gibbs CAM software from Solid Edge Voyager Program member Gibbs and Associates. * Developments * Ariba, Inc. announced that it recently developed a Private Sourcing Exchange for Bristol-Myers Squibb, a $20 billion diversified, global health and personal care company. The Ariba-powered Private Sourcing Exchange is an Internet-based tool for Bristol-Myers Squibb's RFQ-based purchases for direct and indirect materials, business services, and capital assets. Autodesk, Inc. and Digital River, Inc. announced the launch of the Autodesk Partner Products Store, a new service that will allow customers to purchase third-party developer add-on products from members of the Autodesk Developer Network (ADN). CADCAM-E.COM announced the availability of over-the-web translations of CATIA, Unigraphics and Pro/ENGINEER files to AutoCAD Mechanical Desktop. Cadence Design Systems, Inc. announced the release of TestBuilder 1.0, a new version of its testbench C++ class library that now includes a rich library of event expressions and support for VHDL as well as Verilog. Cadence Design Systems, Inc. announced a first-of-its kind wireless solution that incorporates radio frequency and digital signal processing system design, platform-based design, optimization and verification, and data path synthesis. As an integrated platform it is designed to shorten time-to-market for complex wireless products. Cimmetry Systems, Inc. announced the release of AutoVue 15.4, the latest version of its flagship visualization and markup family of products. This family of products includes: AutoVue, AutoVue Professional, AutoVue SolidModel, AutoVue SolidModel Professional. Dassault Systemes announced that Dimensional Control Systems introduced 3DCS On CAA V5, a seamless integration of 3-D tolerance analysis technology into the CATIA V5 environment. eBT International, Inc. announced the release of engenda 4.7, featuring new functionality to simplify workflow development and enhance personalization through advanced integration with BEA WebLogic Personalization Server. Hummingbird Ltd. and Matrix Logic Corporation, a producer of document management system utilities, announced the availability of a mobile document management system. Through Matrix Logic's Wireless DMS Suite users can access documents stored in a Hummingbird Document Management solution from anywhere via mobile phones, personal digital assistants (PDAs) and handheld computers. Innoveda, Inc. announced the release of TransBridge, a wiring topology interface between the company's TransDesign tool suite for electrical system design and SDRC's I-DEAS mechanical design automation software. Maxim I/T and Cimmetry Systems announced the completion of integrating Cimmetry's Web-based viewing technology into Maxim's FindView 2.0.  Modultek announced that it has turned its experience of managing product-related technical information into a solution where all parties, from product management through delivery to customer care share customer solution information. Modultek defines this horizontal CRM functionality as Customer Solution Management. Modultek’s Aton manages up-to-date information on customer specific deliveries and manages the whole product life cycle information. QuadRite Inc., an Application Service Provider, announced it will offer New Product Introduction (NPI) business processes and Product Data Management (PDM) systems as a turnkey outsource service for discrete product design and manufacturing enterprises. RedSpark, Inc., a developer of inter-enterprise applications for the manufacturing industry, announced its RAPIDteam solution. RAPIDteam provides a common platform for project managers, engineers, supply chain managers, and purchasing professionals to work together with their direct material suppliers to accelerate time to market and improve product quality. Engineering Data Management Newsletter RedSpark, Inc. announced its ProductEdge solution. ProductEdge provides an eBusiness platform that is developed specifically for the needs of standard component manufacturers to provide an online product specification environment for their customers. Workgroup Technology Corporation (WTC) announced the immediate availability of its latest ProductCenter PDM solution, ProductCenter Version 7.4. Improvements in the ProductCenter client/server network communications protocol enhance ProductCenter usability and significantly boost its overall performance - with data access functions being accelerated as much as 800%. ZoomON announced its Java based CADViewer viewer for AutoCAD Drawing Web Format (DWF) and SVF. * Relationships * Alventive, Inc. and Cimmetry Systems, Inc. announced that Cimmetry's AutoVue for Java technology will be embedded in the Alventive Collaborative Design Solution Family. CEIMIS Enterprises, Inc, a provider of collaborative Product Lifecycle Management solutions, and Global Factory Inc., a Collaborative Manufacturing Execution (CME) platform provider, announced that they have formed an Alliance Partnership. Cimmetry Systems Inc. and QuadRite, a provider of PDM systems as a turnkey outsource service, announced that QuadRite has licensed Cimmetry's AutoVue technology for use in its RitePro solution. Documentum and diCarta Inc. announced a strategic partnership to increase their reach in the B2B marketplace. diCarta will integrate Documentum 4i B2B Content Management Edition with diCarta Contracts, a B2B contract lifecycle management solution. Documentum and Arbortext, a provider of XML-based software for multi-channel single source publishing, announced plans to jointly market the Documentum 4i B2B Content Management Edition and Arbortext Intermarket catalog solution. Documentum and Menerva Technologies, Inc., a provider of online collaborative negotiation and contract management solutions for enterprises and e-marketplaces, announced that the two companies are teaming to provide enterprise customers with an advanced contract-based e-procurement solution for collaborative commerce. Eurostep Group and PDTec announced that the two organizations have formed a strategic business partnership. PDTec's PDMconnect product allows for seamless integration between a customer's PDM system and Eurostep Group's Share-A-space, a product data sharing portal for engineering collaboration projects. Informative Graphics announced that its Net-It Central Web-Based Publishing solution has been chosen to power document publishing by website development firm Viewpoint Technologies. MXintegrations, a business unit of The van der Roest Group, Inc., announced an enterprise application integration with MatrixOne's eMatrix 9 Intelligent Collaborative Commerce framework for Lotus Notes. MatrixOne, Inc. and MITEM Corp., a provider of legacy integration software for conducting real-time e-Business, announced the integration of MitemView into MatrixOne's eMatrix platform. This agreement will enable MatrixOne customers to access data and transactions from virtually any legacy system. MatrixOne, Inc. and Cap Gemini Ernst & Young announced an alliance to deliver product collaboration and net market solutions for a variety of industries. Modultek Oy announced that it concluded a partner agreement with Exertus AB, Sweden in March, 2001. The agreement consists of retail, consulting, implementing, and training of Modultek's Customer Solution Management software solution, Aton. b2bScene, a division of Open Text Corporation, announced that in preparation for the upcoming launch of its vertical industry solutions and to meet the needs of its largest customers, it has bolstered its hosting and security infrastructure by joining the Exodus Communications Partnering for Success Alliance Partner program. Paraform Inc. announced it has signed an agreement with Oculus Technologies extending real-time application linking of disparate business systems for its Collaborative Innovation Platform (CIP). PTC announced a reseller partnership with value-added reseller Topologies Ltd. of Daventry, England. According to the terms of the agreement, Topologies Ltd. will be the sole distributor to the British transportation market for ICEM Surf. Topologies will also resell other ICEM Technologies surfacing products, including CDRS and 3DPAINT. Smart Solutions announced that it has joined the Primavera Systems, Inc. Partner Program. Primavera is a developer of enterprise and Web-based project management, control and execution software. Smart Solutions announced it joined RosettaNet, a self-funded and non-profit consortium of major information technology, electronic component, and semiconductor manufacturing companies working to create and implement industry-wide, open e-business process standards. Smart Solutions announced the formation of a partnership with Océ-USA, Inc. whereby the two companies will integrate the Océ Engineering Exec suite of enterprise print management solutions with SmarTeam's collaborative product commerce offerings. Spicer Corporation and MatrixOne, Inc. announced that they have joined forces to offer Spicer's ViewCafé to MatrixOne's eMatrix customers. ViewCafé offers eMatrix users such functions as full resolution printing, ISO-compliant print banners and thumbnail previews of documents. Spicer Corporation announced that MightyCar Service Co., Ltd. has signed an agreement to be the exclusive distribution representative of Spicer products in Japan. Headquartered in Tokyo, MightyCar will distribute Spicer technologies to value added resellers through its software solution subsidiary StarCommerce Co., Ltd. and provide sales, marketing, and customer support for Spicer's client- and server-based document visualization software. Tecnomatix Technologies Ltd. announced a long-term agreement whereby Tecnomatix will integrate RealityWave's VizStream technology into its eMPower offering UGS announced a partnership with iWay Software, an Information Builders company, that links product definition information with additional related data stored on mainframes or back-office enterprise systems. * Other * Autodesk, Inc. announced that it will provide 2,500 Compaq iPAQ Pocket PC handhelds to its worldwide sales force and channel partners. The iPAQ Pocket PCs will provide real-time access to online sales and product information right at the point of work. Cypress Corporation announced full product support for the Electronic Signatures in Global and National Commerce Act (ESIGN). Dassault Systemes announced that it now supports the ENOVIA DMU Navigator, part of the ENOVIA Portal Solutions, on next-generation Intel Itanium Processor-Based Systems. Digital Paper Corporation reported strong industry response to its recently announced hosted application solution, myDigitalPaper. Documentum announced that it has completed a proof of concept demonstration of the emerging ebXML global messaging standard. The ebXML Initiative was jointly established by UN/CEFACT and OASIS. Hewlett-Packard Company announced the creation of a new business unit chartered with accelerating the growth of its IT services business. Ann Livermore has been named president of the new operating unit and will report directly to Carly Fiorina, HP chairman, president and CEO. MatrixOne, Inc. announced its plans for the opening of its Asia-Pacific customer success center in Korea. The new office will act as the center for MatrixOne's North Asia operations. Océ announced the introduction of the I-Magic Box, a marketing program intended to support Document Production Center managers in promoting added value to their company's departments and end-users. SolidWorks Corporation announced that it will now include SolidWorks Toolbox in its educational design software package for students and educators, making product design faster and easier by giving them instant access to a library of standard parts. SolidWorks Toolbox provides design automation and drafting annotation tools, as well as access to a wide variety of standard components. Formerly offered as a partner application called Toolbox/SE, the product was recently renamed SolidWorks Toolbox following SolidWorks Corporation's November 2000 acquisition of CIMLOGIC. Staffware announced that it has gained the highest overall ranking in the 2001 edition of Workflow and Groupware Strategies' (W&GS) Workflow Comparative Study. 13 workflow products were analyzed and ranked. Staffware came in the top three in more categories than any other product. STEP Tools, Inc. announced it will open the North American Center for STEP-NC Technology on Wednesday, June 6, 2001. The center will be located in downtown Troy, NY across from the company's headquarters in the Rice Building. VIDAR Systems Corporation announced a Worldwide Partner Online Forum - PartnerNet. PartnerNet was developed as a message board for VIDAR worldwide partners and employees to share information, comments and questions about VIDAR products and solutions. PartnerNet is set up with five different forums with moderators for each. The five forums consist of black-and-white products, color products, technical discussions, sales and marketing, and software. |
Brief lines | To subscribe to 2PDM, fill in the subscription form or send an e-mail headed 'start 2PDM subscription' to pdm@2pdm.com Subscription cost Subscribers receive 2PDM free of charge. Privacy policy We understand and respect your desire for privacy. The information we ask for at subscription time is the minimum necessary to effectively fulfill your subscription and communicate with you if and when necessary. We do not release the information you provide us to third parties. In case of further questions, you can reach us at pdm@2pdm.com Previous issues Click here to access previous issues of 2PDM. Limited time We know you have a busy schedule. To reduce delivery and reading time, 2PDM has a simple format and concise content. Termination of subscription To terminate subscription, please send an e-mail headed 'stop 2PDM subscription' to pdm@2pdm.com Sponsorship 2PDM is provided free of charge to its readers. Companies that share our objectives of promoting successful implementation of EDM and PDM systems and world-class product development performance may sponsor 2PDM. There is space for a maximum of one sponsor message per page, except on this 'Brief lines' page - where there is room for several short sponsor messages. Publication frequency 2PDM is published approximately every two weeks. Copyright Copyright 2001 by John Stark. All rights reserved. Permission to reproduce text or graphics Applications for permission to reproduce part or parts of 2PDM (text or graphics) should be sent to pdm@2pdm.com Permission to make 2PDM available within an organization Applications for permission to make 2PDM available within a company or other organization (e.g. by internal mail, corporate Intranet, etc.) are usually accepted. Please send a request for permission to pdm@2pdm.com Disclaimer Information provided in 2PDM is intended solely to provide general guidance on matters of interest for the personal use of the reader, who accepts full responsibility for its use. Information is provided 'as is', with no guarantee of completeness, accuracy, or timeliness, and without warranty of any kind, express or implied, including, but not limited to, the warranties of performance, merchantability, and fitness for a particular purpose. Nothing in 2PDM shall to any extent substitute for the independent investigations and the sound technical and business judgement of the reader. Technology, laws and regulations are continually changing, and can only be interpreted in the light of particular factual situations. The information in 2PDM does not constitute technological, business, legal, investment or consulting advice, and should only be used in conjunction with appropriate professional advice obtained by the reader from a suitably qualified professional who understands the reader's particular factual situation. |